A prior art television system containing a built-in multiple function audio system has left and right speakers for receiving stereo audio or two-tone audio. FIG. 14 shows such a television set.
The television set shown in FIG. 14 and FIG. 15 includes a television set cabinet 11, a cathode ray tube 12, a left front speaker 13, and a right front speaker 14. The speakers 13 and 14 are positioned on the front panel of the television cabinet 11. In FIG. 15, the direction and spread of the sound waves emanating from the speakers 14 and 15 are represented when the television set is located in a room 18.
According to the prior art, the speakers in a television have been located either on each side of the cathode ray tube screen or above and below the cathode ray tube screen. Recently, since larger wide-screen television sets have become popular, screens have increased in size. The feasibility of such wide-screen television sets depends on the user's ability to fit the larger screen television set in a room at home. With space being an important purchaser concern, television sets are being designed to minimize the size of the unit. Accordingly, the space for installation of speaker units on television sets has become increasingly smaller.
Thus, relatively small speakers positioned around the cathode ray tube screen reproduce the audio for the television set. Consequently, the system lacks a "live" feeling as if the listener were attending a live event, e.g., a concert, with little sense of stereo sound such as movement of sound from left speaker to right speaker.
Since the distance between the left and right speakers on a television set is short, the stereo sound is relatively poor when compared with the stereo sound of a speaker arrangement associated with a typical stereo system. Currently, high definition and wide-screen televisions with an aspect ratio of 16:9 are entering the marketplace. These televisions are wider than conventional televisions. Thus, to minimize the increase in size of the television set due to wider screens, narrow slim style speakers positioned on each side of the television set have been used. However, the reproduction of good-sounding stereo audio remains a problem.
Apart from television sets, in the general audio field non-directional speaker systems which employ reflectors have been used. FIG. 16 is a vertical cross-section of a non-directional speaker system. The speaker system includes a speaker cabinet 21, a speaker for low-frequency sound (woofer) 22, a speaker for high-frequency sound (tweeter) 23, a non-directional reflection speaker 24, a non-directional conical reflector 25, and a netting 26 for holding the non-directional reflector 25 above the non-directional speaker 24. The FIG. 16 system attempts to improve the sound in a horizontal direction. Sound can be radiated in the horizontal direction by roughly positioning the conical reflector 25 in front of the reflection speaker 24 which faces in an upward direction perpendicular to the direction in which the sound radiates, as opposed to speakers 22 and 23 which radiate the sound in a forward direction.
Another system on the market, depicted in FIG. 17, in which speakers 13 and 14 are fitted on both sides of the cathode ray tube 12 on the television set cabinet 11. Sound outputted from the speakers 14 and 15 reflects off the reflectors 15 and 16 positioned on both sides of the television set. Such an outputting arrangement is necessary because the cathode ray tube 12 occupies a large area so that to minimize the size of the television set, the speakers 13 and 14 are located on the side thereof. Therefore, to direct the sound in a forward direction relative to the television set when the speakers 13 and 14 are located on the side of the television set cabinet, the reflectors 15 and 16 must be employed.
However, with the system of FIG. 17, it is difficult to manufacture the reflectors 15 and 16 to properly protrude from the side of the television cabinet 11. Further, the "live" feeling and quality stereo sound cannot be fully achieved.
In a high definition broadcast system, stereophonic sound can be achieved by using a 3-1 system 4-channel stereo. Thus, by using a speech dedicated center speaker, two front speakers as left and right speakers and a "surround" rear speaker, stereophonic sound from four directions can be achieved.
FIG. 18 shows a prior art style 3-1 system 4-channel stereo in a television set speaker system. This embodiment includes a television cabinet set 11, a cathode ray tube 12, left and right front stereo speakers 13 and 14, and a speech dedicated center 17. An external speaker (not illustrated) may be plugged into terminals located at the back of the television set cabinet 11. According to this arrangement, the sound is concentrated on the center channel, therefore providing clear sound reproduction. However, the sound becomes flat like in a monaural system and an accompanying reduction in stereophonic quality occurs. Additionally, a space problem results with the positioning of three speakers in front of the television set.